Non-insulin dependent diabetes (NIDDM) is associated with increased risk for coronary artery, peripheral vascular, and cerebrovascular diseases. It has been hypothesized that cardiovascular disease (CVD) is not a consequence of NIDDM but that both conditions share common antecedents. Risk factors such as obesity, high fasting plasma glucose and total and low-density lipoprotein cholesterol concentrations with low levels of high-density lipoprotein cholesterol, high blood pressure -- all cluster in normoglycemic subjects who subsequently develop impaired glucose tolerance. This study proposes to determine if insulin resistance is associated with increased prevalence of CVD independent of obesity, glycemia, and insulinemia, to determine the impact of insulin resistance on CVD risk factors, to determine if there are ethnic differences in the relationship between insulin resistance and the prevalence of CVD, and to establish the basis for a prospective study to determine if insulin resistance predicts the development of CVD and its risk factors.